[PATCH v4 2/3] gpio/mxs: Change gpio-mxs into an upstanding gpio driver

From: Shawn Guo
Date: Sun Jun 05 2011 - 11:51:29 EST

The patch makes necessary changes on gpio-mxs as below to turn it
into an upstanding gpio driver.

* Clean up the gpio port definition stuff

* Use readl/writel to replace mach-specific accessors
__raw_readl/__raw_writel

* Change mxs_gpio_init into mxs_gpio_probe function

And it then migrates mach-mxs to the updated driver by adding
corresponding platform devices.

Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx>
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/arm/mach-mxs/devices.c | 11 ++
arch/arm/mach-mxs/devices/Makefile | 1 +
arch/arm/mach-mxs/devices/platform-gpio-mxs.c | 53 ++++++
arch/arm/mach-mxs/include/mach/devices-common.h | 2 +
arch/arm/mach-mxs/mm-mx23.c | 1 -
arch/arm/mach-mxs/mm-mx28.c | 1 -
drivers/gpio/gpio-mxs.c | 216 +++++++++++++----------
7 files changed, 191 insertions(+), 94 deletions(-)
create mode 100644 arch/arm/mach-mxs/devices/platform-gpio-mxs.c

diff --git a/arch/arm/mach-mxs/devices.c b/arch/arm/mach-mxs/devices.c
index cfdb6b2..fe3e847 100644
--- a/arch/arm/mach-mxs/devices.c
+++ b/arch/arm/mach-mxs/devices.c
@@ -88,3 +88,14 @@ int __init mxs_add_amba_device(const struct amba_device *dev)

return amba_device_register(adev, &iomem_resource);
}
+
+struct device mxs_apbh_bus = {
+ .init_name = "mxs_apbh",
+ .parent = &platform_bus,
+};
+
+static int __init mxs_device_init(void)
+{
+ return device_register(&mxs_apbh_bus);
+}
+core_initcall(mxs_device_init);
diff --git a/arch/arm/mach-mxs/devices/Makefile b/arch/arm/mach-mxs/devices/Makefile
index 324f282..351915c 100644
--- a/arch/arm/mach-mxs/devices/Makefile
+++ b/arch/arm/mach-mxs/devices/Makefile
@@ -6,4 +6,5 @@ obj-$(CONFIG_MXS_HAVE_PLATFORM_FLEXCAN) += platform-flexcan.o
obj-$(CONFIG_MXS_HAVE_PLATFORM_MXS_I2C) += platform-mxs-i2c.o
obj-$(CONFIG_MXS_HAVE_PLATFORM_MXS_MMC) += platform-mxs-mmc.o
obj-$(CONFIG_MXS_HAVE_PLATFORM_MXS_PWM) += platform-mxs-pwm.o
+obj-y += platform-gpio-mxs.o
obj-$(CONFIG_MXS_HAVE_PLATFORM_MXSFB) += platform-mxsfb.o
diff --git a/arch/arm/mach-mxs/devices/platform-gpio-mxs.c b/arch/arm/mach-mxs/devices/platform-gpio-mxs.c
new file mode 100644
index 0000000..ed0885e
--- /dev/null
+++ b/arch/arm/mach-mxs/devices/platform-gpio-mxs.c
@@ -0,0 +1,53 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+#include <linux/compiler.h>
+#include <linux/err.h>
+#include <linux/init.h>
+
+#include <mach/mx23.h>
+#include <mach/mx28.h>
+#include <mach/devices-common.h>
+
+struct platform_device *__init mxs_add_gpio(
+ int id, resource_size_t iobase, int irq)
+{
+ struct resource res[] = {
+ {
+ .start = iobase,
+ .end = iobase + SZ_8K - 1,
+ .flags = IORESOURCE_MEM,
+ }, {
+ .start = irq,
+ .end = irq,
+ .flags = IORESOURCE_IRQ,
+ },
+ };
+
+ return platform_device_register_resndata(&mxs_apbh_bus,
+ "gpio-mxs", id, res, ARRAY_SIZE(res), NULL, 0);
+}
+
+static int __init mxs_add_mxs_gpio(void)
+{
+ if (cpu_is_mx23()) {
+ mxs_add_gpio(0, MX23_PINCTRL_BASE_ADDR, MX23_INT_GPIO0);
+ mxs_add_gpio(1, MX23_PINCTRL_BASE_ADDR, MX23_INT_GPIO1);
+ mxs_add_gpio(2, MX23_PINCTRL_BASE_ADDR, MX23_INT_GPIO2);
+ }
+
+ if (cpu_is_mx28()) {
+ mxs_add_gpio(0, MX28_PINCTRL_BASE_ADDR, MX28_INT_GPIO0);
+ mxs_add_gpio(1, MX28_PINCTRL_BASE_ADDR, MX28_INT_GPIO1);
+ mxs_add_gpio(2, MX28_PINCTRL_BASE_ADDR, MX28_INT_GPIO2);
+ mxs_add_gpio(3, MX28_PINCTRL_BASE_ADDR, MX28_INT_GPIO3);
+ mxs_add_gpio(4, MX28_PINCTRL_BASE_ADDR, MX28_INT_GPIO4);
+ }
+
+ return 0;
+}
+postcore_initcall(mxs_add_mxs_gpio);
diff --git a/arch/arm/mach-mxs/include/mach/devices-common.h b/arch/arm/mach-mxs/include/mach/devices-common.h
index 7a37469..812d7a8 100644
--- a/arch/arm/mach-mxs/include/mach/devices-common.h
+++ b/arch/arm/mach-mxs/include/mach/devices-common.h
@@ -11,6 +11,8 @@
#include <linux/init.h>
#include <linux/amba/bus.h>

+extern struct device mxs_apbh_bus;
+
struct platform_device *mxs_add_platform_device_dmamask(
const char *name, int id,
const struct resource *res, unsigned int num_resources,
diff --git a/arch/arm/mach-mxs/mm-mx23.c b/arch/arm/mach-mxs/mm-mx23.c
index 5148cd6..1b2345a 100644
--- a/arch/arm/mach-mxs/mm-mx23.c
+++ b/arch/arm/mach-mxs/mm-mx23.c
@@ -41,5 +41,4 @@ void __init mx23_map_io(void)
void __init mx23_init_irq(void)
{
icoll_init_irq();
- mx23_register_gpios();
}
diff --git a/arch/arm/mach-mxs/mm-mx28.c b/arch/arm/mach-mxs/mm-mx28.c
index 7e4cea3..b6e18dd 100644
--- a/arch/arm/mach-mxs/mm-mx28.c
+++ b/arch/arm/mach-mxs/mm-mx28.c
@@ -41,5 +41,4 @@ void __init mx28_map_io(void)
void __init mx28_init_irq(void)
{
icoll_init_irq();
- mx28_register_gpios();
}
diff --git a/drivers/gpio/gpio-mxs.c b/drivers/gpio/gpio-mxs.c
index bac7b6b..6fd9f01 100644
--- a/drivers/gpio/gpio-mxs.c
+++ b/drivers/gpio/gpio-mxs.c
@@ -25,13 +25,13 @@
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/gpio.h>
-#include <mach/mx23.h>
-#include <mach/mx28.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <mach/mxs.h>
#include <mach/gpio-mxs.h>
-#include <asm-generic/bug.h>

-static struct mxs_gpio_port *mxs_gpio_ports;
-static int gpio_table_size;
+#define MXS_SET 0x4
+#define MXS_CLR 0x8

#define PINCTRL_DOUT(n) ((cpu_is_mx23() ? 0x0500 : 0x0700) + (n) * 0x10)
#define PINCTRL_DIN(n) ((cpu_is_mx23() ? 0x0600 : 0x0900) + (n) * 0x10)
@@ -53,36 +53,42 @@ static int gpio_table_size;

static void clear_gpio_irqstatus(struct mxs_gpio_port *port, u32 index)
{
- __mxs_clrl(1 << index, port->base + PINCTRL_IRQSTAT(port->id));
+ writel(1 << index, port->base + PINCTRL_IRQSTAT(port->id) + MXS_CLR);
}

static void set_gpio_irqenable(struct mxs_gpio_port *port, u32 index,
int enable)
{
if (enable) {
- __mxs_setl(1 << index, port->base + PINCTRL_IRQEN(port->id));
- __mxs_setl(1 << index, port->base + PINCTRL_PIN2IRQ(port->id));
+ writel(1 << index,
+ port->base + PINCTRL_IRQEN(port->id) + MXS_SET);
+ writel(1 << index,
+ port->base + PINCTRL_PIN2IRQ(port->id) + MXS_SET);
} else {
- __mxs_clrl(1 << index, port->base + PINCTRL_IRQEN(port->id));
+ writel(1 << index,
+ port->base + PINCTRL_IRQEN(port->id) + MXS_CLR);
}
}

static void mxs_gpio_ack_irq(struct irq_data *d)
{
+ struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
u32 gpio = irq_to_gpio(d->irq);
- clear_gpio_irqstatus(&mxs_gpio_ports[gpio / 32], gpio & 0x1f);
+ clear_gpio_irqstatus(port, gpio & 0x1f);
}

static void mxs_gpio_mask_irq(struct irq_data *d)
{
+ struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
u32 gpio = irq_to_gpio(d->irq);
- set_gpio_irqenable(&mxs_gpio_ports[gpio / 32], gpio & 0x1f, 0);
+ set_gpio_irqenable(port, gpio & 0x1f, 0);
}

static void mxs_gpio_unmask_irq(struct irq_data *d)
{
+ struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
u32 gpio = irq_to_gpio(d->irq);
- set_gpio_irqenable(&mxs_gpio_ports[gpio / 32], gpio & 0x1f, 1);
+ set_gpio_irqenable(port, gpio & 0x1f, 1);
}

static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset);
@@ -91,7 +97,7 @@ static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
{
u32 gpio = irq_to_gpio(d->irq);
u32 pin_mask = 1 << (gpio & 31);
- struct mxs_gpio_port *port = &mxs_gpio_ports[gpio / 32];
+ struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);
void __iomem *pin_addr;
int edge;

@@ -115,16 +121,16 @@ static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
/* set level or edge */
pin_addr = port->base + PINCTRL_IRQLEV(port->id);
if (edge & GPIO_INT_LEV_MASK)
- __mxs_setl(pin_mask, pin_addr);
+ writel(pin_mask, pin_addr + MXS_SET);
else
- __mxs_clrl(pin_mask, pin_addr);
+ writel(pin_mask, pin_addr + MXS_CLR);

/* set polarity */
pin_addr = port->base + PINCTRL_IRQPOL(port->id);
if (edge & GPIO_INT_POL_MASK)
- __mxs_setl(pin_mask, pin_addr);
+ writel(pin_mask, pin_addr + MXS_SET);
else
- __mxs_clrl(pin_mask, pin_addr);
+ writel(pin_mask, pin_addr + MXS_CLR);

clear_gpio_irqstatus(port, gpio & 0x1f);

@@ -135,13 +141,13 @@ static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc)
{
u32 irq_stat;
- struct mxs_gpio_port *port = (struct mxs_gpio_port *)irq_get_handler_data(irq);
+ struct mxs_gpio_port *port = irq_get_handler_data(irq);
u32 gpio_irq_no_base = port->virtual_irq_start;

desc->irq_data.chip->irq_ack(&desc->irq_data);

- irq_stat = __raw_readl(port->base + PINCTRL_IRQSTAT(port->id)) &
- __raw_readl(port->base + PINCTRL_IRQEN(port->id));
+ irq_stat = readl(port->base + PINCTRL_IRQSTAT(port->id)) &
+ readl(port->base + PINCTRL_IRQEN(port->id));

while (irq_stat != 0) {
int irqoffset = fls(irq_stat) - 1;
@@ -163,7 +169,7 @@ static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
{
u32 gpio = irq_to_gpio(d->irq);
u32 gpio_idx = gpio & 0x1f;
- struct mxs_gpio_port *port = &mxs_gpio_ports[gpio / 32];
+ struct mxs_gpio_port *port = irq_data_get_irq_chip_data(d);

if (enable) {
if (port->irq_high && (gpio_idx >= 16))
@@ -197,9 +203,9 @@ static void mxs_set_gpio_direction(struct gpio_chip *chip, unsigned offset,
void __iomem *pin_addr = port->base + PINCTRL_DOE(port->id);

if (dir)
- __mxs_setl(1 << offset, pin_addr);
+ writel(1 << offset, pin_addr + MXS_SET);
else
- __mxs_clrl(1 << offset, pin_addr);
+ writel(1 << offset, pin_addr + MXS_CLR);
}

static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset)
@@ -207,7 +213,7 @@ static int mxs_gpio_get(struct gpio_chip *chip, unsigned offset)
struct mxs_gpio_port *port =
container_of(chip, struct mxs_gpio_port, chip);

- return (__raw_readl(port->base + PINCTRL_DIN(port->id)) >> offset) & 1;
+ return (readl(port->base + PINCTRL_DIN(port->id)) >> offset) & 1;
}

static void mxs_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
@@ -217,9 +223,9 @@ static void mxs_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
void __iomem *pin_addr = port->base + PINCTRL_DOUT(port->id);

if (value)
- __mxs_setl(1 << offset, pin_addr);
+ writel(1 << offset, pin_addr + MXS_SET);
else
- __mxs_clrl(1 << offset, pin_addr);
+ writel(1 << offset, pin_addr + MXS_CLR);
}

static int mxs_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
@@ -244,87 +250,113 @@ static int mxs_gpio_direction_output(struct gpio_chip *chip,
return 0;
}

-int __init mxs_gpio_init(struct mxs_gpio_port *port, int cnt)
+static int __devinit mxs_gpio_probe(struct platform_device *pdev)
{
- int i, j;
+ static void __iomem *base;
+ struct mxs_gpio_port *port;
+ struct resource *iores = NULL;
+ int err, i;
+
+ port = kzalloc(sizeof(struct mxs_gpio_port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ port->id = pdev->id;
+ port->virtual_irq_start = MXS_GPIO_IRQ_START + port->id * 32;
+
+ /*
+ * map memory region only once, as all the gpio ports
+ * share the same one
+ */
+ if (!base) {
+ iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!iores) {
+ err = -ENODEV;
+ goto out_kfree;
+ }

- /* save for local usage */
- mxs_gpio_ports = port;
- gpio_table_size = cnt;
+ if (!request_mem_region(iores->start, resource_size(iores),
+ pdev->name)) {
+ err = -EBUSY;
+ goto out_kfree;
+ }

- pr_info("MXS GPIO hardware\n");
+ base = ioremap(iores->start, resource_size(iores));
+ if (!base) {
+ err = -ENOMEM;
+ goto out_release_mem;
+ }
+ }
+ port->base = base;

- for (i = 0; i < cnt; i++) {
- /* disable the interrupt and clear the status */
- __raw_writel(0, port[i].base + PINCTRL_PIN2IRQ(i));
- __raw_writel(0, port[i].base + PINCTRL_IRQEN(i));
+ port->irq = platform_get_irq(pdev, 0);
+ if (port->irq < 0) {
+ err = -EINVAL;
+ goto out_iounmap;
+ }

- /* clear address has to be used to clear IRQSTAT bits */
- __mxs_clrl(~0U, port[i].base + PINCTRL_IRQSTAT(i));
+ /* disable the interrupt and clear the status */
+ writel(0, port->base + PINCTRL_PIN2IRQ(port->id));
+ writel(0, port->base + PINCTRL_IRQEN(port->id));

- for (j = port[i].virtual_irq_start;
- j < port[i].virtual_irq_start + 32; j++) {
- irq_set_chip_and_handler(j, &gpio_irq_chip,
- handle_level_irq);
- set_irq_flags(j, IRQF_VALID);
- }
+ /* clear address has to be used to clear IRQSTAT bits */
+ writel(~0U, port->base + PINCTRL_IRQSTAT(port->id) + MXS_CLR);

- /* setup one handler for each entry */
- irq_set_chained_handler(port[i].irq, mxs_gpio_irq_handler);
- irq_set_handler_data(port[i].irq, &port[i]);
-
- /* register gpio chip */
- port[i].chip.direction_input = mxs_gpio_direction_input;
- port[i].chip.direction_output = mxs_gpio_direction_output;
- port[i].chip.get = mxs_gpio_get;
- port[i].chip.set = mxs_gpio_set;
- port[i].chip.to_irq = mxs_gpio_to_irq;
- port[i].chip.base = i * 32;
- port[i].chip.ngpio = 32;
-
- /* its a serious configuration bug when it fails */
- BUG_ON(gpiochip_add(&port[i].chip) < 0);
+ for (i = port->virtual_irq_start;
+ i < port->virtual_irq_start + 32; i++) {
+ irq_set_chip_and_handler(i, &gpio_irq_chip,
+ handle_level_irq);
+ set_irq_flags(i, IRQF_VALID);
+ irq_set_chip_data(i, port);
}

- return 0;
-}
+ /* setup one handler for each entry */
+ irq_set_chained_handler(port->irq, mxs_gpio_irq_handler);
+ irq_set_handler_data(port->irq, port);

-#define MX23_GPIO_BASE MX23_IO_ADDRESS(MX23_PINCTRL_BASE_ADDR)
-#define MX28_GPIO_BASE MX28_IO_ADDRESS(MX28_PINCTRL_BASE_ADDR)
+ /* register gpio chip */
+ port->chip.direction_input = mxs_gpio_direction_input;
+ port->chip.direction_output = mxs_gpio_direction_output;
+ port->chip.get = mxs_gpio_get;
+ port->chip.set = mxs_gpio_set;
+ port->chip.to_irq = mxs_gpio_to_irq;
+ port->chip.base = port->id * 32;
+ port->chip.ngpio = 32;

-#define DEFINE_MXS_GPIO_PORT(_base, _irq, _id) \
- { \
- .chip.label = "gpio-" #_id, \
- .id = _id, \
- .irq = _irq, \
- .base = _base, \
- .virtual_irq_start = MXS_GPIO_IRQ_START + (_id) * 32, \
- }
+ err = gpiochip_add(&port->chip);
+ if (err)
+ goto out_iounmap;

-#ifdef CONFIG_SOC_IMX23
-static struct mxs_gpio_port mx23_gpio_ports[] = {
- DEFINE_MXS_GPIO_PORT(MX23_GPIO_BASE, MX23_INT_GPIO0, 0),
- DEFINE_MXS_GPIO_PORT(MX23_GPIO_BASE, MX23_INT_GPIO1, 1),
- DEFINE_MXS_GPIO_PORT(MX23_GPIO_BASE, MX23_INT_GPIO2, 2),
-};
+ return 0;

-int __init mx23_register_gpios(void)
-{
- return mxs_gpio_init(mx23_gpio_ports, ARRAY_SIZE(mx23_gpio_ports));
+out_iounmap:
+ if (iores)
+ iounmap(port->base);
+out_release_mem:
+ if (iores)
+ release_mem_region(iores->start, resource_size(iores));
+out_kfree:
+ kfree(port);
+ dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err);
+ return err;
}
-#endif
-
-#ifdef CONFIG_SOC_IMX28
-static struct mxs_gpio_port mx28_gpio_ports[] = {
- DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO0, 0),
- DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO1, 1),
- DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO2, 2),
- DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO3, 3),
- DEFINE_MXS_GPIO_PORT(MX28_GPIO_BASE, MX28_INT_GPIO4, 4),
+
+static struct platform_driver mxs_gpio_driver = {
+ .driver = {
+ .name = "gpio-mxs",
+ .owner = THIS_MODULE,
+ },
+ .probe = mxs_gpio_probe,
};

-int __init mx28_register_gpios(void)
+static int __init mxs_gpio_init(void)
{
- return mxs_gpio_init(mx28_gpio_ports, ARRAY_SIZE(mx28_gpio_ports));
+ return platform_driver_register(&mxs_gpio_driver);
}
-#endif
+postcore_initcall(mxs_gpio_init);
+
+MODULE_AUTHOR("Freescale Semiconductor, "
+ "Daniel Mack <danielncaiaq.de>, "
+ "Juergen Beisert <kernel@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Freescale MXS GPIO");
+MODULE_LICENSE("GPL");
--
1.7.4.1

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